Thermionic repeater.



A. McL. NICOLSON. THERMIONIC REPEATER.

APPLICATION FILED SEPT-23; 1914.

1 15 422, Patented Jan. 25, 1916.

M Affy.

ALEXANDER McLEAN' NICOLSON,

OF TARRYTOWN, NEW YORK, ASSIGNOR, BY'MESNE ASSIGNMENTS, T0 WESTERNELECTRIC COMPANY, INCORPORATED, A CORPORATION OF NEW YORK.v

Continuation of application Serial No.-

THERMIONIC BEPEATEB.

Specification of Letters Patent.

Patented an 843,502, filed June 6, 1914. This application filedSeptember 23,

1914. Serial No. 863,209.

To all whom it may concern:

Be it known that I, ALEXANDER MCLEAN NiconsoN, a subject of the King ofGreat Britain, residing at T arrytown, in the county of WVestchester andState of New York, have invented certain new and useful Improvements inThermionic Repeaters, of which the following is a full, clear, concise,and 'exact description.

This application is a continuation of an application by 'this applicant,Serial 'No. 843,502, filed June 6, 1914.

..The invention relates to thermionic repeaters such as audions, and itsobject is to improve the efiiciency thereof.

It has been found that the closer the input electrode and the cathodeare brought together, the stronger the electric field and the. moreefiicient the control of the thermionic current. This is true whetherthe repeater be one, say of the audion type, having a high-voltageoutput or one having a highcurrent output. The bringing of these twoelements into as close relation to each other as possible withoutpermitting them to contact electrically is brought about, in accordancewith the present invention, by arranging them on opposite sides of, andpreferably touching the opposing surfaces of a dielectric film.Furthermore, the interposed film is greatly beneficial in that itenables the amplifying efliciency of the audion to be increased bypermitting the input electrode to be insulatively supported inexceedingly close relationship to the cathode. It has also been foundthat in the high-current output audion, it is desirable that the cathodepresent a large active area and that the input electrode present minimumobstruc tion between the cathode and the input electrode. Thesedesirable features may best be obtained by entwining the two elements asby winding a filament directly about the input electrode. ably consistsof one or more wires having and the insulating coating preferablyconsists of a thin film of nickelous oxid, such coating having beenfound in practice to be a good dielectric for the purposes-of thisinvention.

The invention may be more readly understood by reference to theaccompanying plates 3,

The input electrode prefer-.

drawing showing in perspective a high-curpent output audion embodyingthe inven- Referring to the drawing, the input electrode is shown in theform of twoparallel wires 1, 1 electrically connected together, or inother words, as consisting of a single wire bent into U shape to providethe two forks 1, 1. The two forks or wires 1, 1 are coated with asuitable dielectric, such, for example, as nickelous oxid, which hasbeen found to be very satisfactory and eflicient for this purpose.

In the case of the high-current output audion illustrated in thedrawing, the oathode is a heated filament 2 entwinedabout the two forksor wires 1, 1, thus presenting a large, active area. The outputelectrode is in the form of two plates 3, 3 parallel to each other andto the plane of the two wires 1, 1 and upon opposite sides thereof. Thetwo 3 are electrically connected together, and since the audion shown isof the high-current output type, said plates are placed near to thefilament. The input electrode, the output electrode and the filament areinclosed as usual in an evacuated bulb 4, and the leading-in wires ofthe aforementioned elements of the audion are sealed in said bulb. meanta repeater depending for its operation upon electron discharge from aheated cathode.

The invention is illustrated and claimed herein as applied to the audionwhich is believed to be the best type of thermionic repeater. In itsbroadest aspect, however, the invention is not limited to the particularstructure herein illustrated but may be found useful in modified formsor types of thermionic repeaters.

What is claimed is:

1. A thermionic repeater having its input electrode and cathodeentwined.

2. A thermionic repeater having its cathode wound upon its inputelectrode.

3. A thermionic repeater having its cathode entwined upon its inputelectrode.

4. A thermionic repeater having its input electrode in the form of awire and having its cathode entwined about said wire.

' 5. A thermionic repeater having its input By thermionic repeater 1selectrode in the form of a plurality of wires and having its cathodeentwined about said \VIIQS.

6. A thermionic repeater having its input electrode in the form of aplurality of parallel wires and its cathode entwined about said wires.

7. A thermionic repeater having its input electrode coated with adielectric and its cathode entwined upon said electrode.

8. A thermionic repeater having its'input electrode coated withnickelous oxid and its cathode entwined upon said electrode.

9. A thermionic repeaterhaving its input electrode coated with nickelousoxid and its cathode in contact with said coated electrode.

10. A thermionic repeater having its input electrode coated with an oxidand its cathode entwined upon said electrode.

11. A thermionic repeater having an input electrode and a cathode, oneof said elements being coated with a dielectric and the other beingentwined upon the former.

12. A thermionic repeater having an inputelectrode and a cathode, one ofsaid elements being coated with an oxid and the other entwined upon theformer.

. 13. A thermionic repeater having an input electrode and a cathode, oneof said elements being coated with nickelous oxid and the other entwinedupon the former.

14. A thermionic repeater having an illput electrode and a cathode, oneof said elements being coated with a dielectric and the other in contactwith the coated element.

15. A thermionic repeater having an input electrode and 'a cathode, andan interposed separating film of non-conducting material in contact withboth.

16. A thermionic repeater having an input electrode and a cathode, andan interposed film of insulating material carried by one of saidelements and with which the other element contacts.

17. A thermionic repeater having an input electrode and a cathodearranged so close together as to permit the interposition of a thin filmonly, and a thin insulating filin between said input electrode and saidcathode.

18. A thermionic repeater having an input electrode and a cathodearranged in close proximity and held out of electrical contact with oneanother by an interposed dielectric.

19. A thermionic repeater having an input electrode and a cathode inimmediate proximity to each other, and one supported y but held out ofelectrical contact with the other by an interposed dielectric.

20. A thermionic repeater having an input electrode and a cathode, and acovering of insulating material carried by one of said elements and withwhich the other element contacts.

21. A thermionic repeater having its cathode arranged between its inputand output electrodes, and an interposed dielectric between said cathodeand said input electrode.

22. A thermionic repeater comprising an input electrode, an outputelectrode and a cathode, said input electrode and said cathode beingseparated byan interposed dielectric film only, and said outputelectrode and said cathode being separated by vacuous space.

In witness whereof, I hereunto subscribe my name-this 22dda-y ofSeptember A. D.,

ALEXANDER MOLEAN NICOLSON. WVitnesses:

1a. EDLER,

K. L. STAHL.

